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Square D QO320-1021 QO3201021 - 20A 3 Pole Miniature Circuit Breaker
- 20A
- 3 Pole
- Plug-On
Square D
QO320-1021
QO3201021 - 20A 3 Pole Miniature Circuit Breaker
Brand
Square D
SKU
QO320-1021
Quantity
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Square D QO3201021 - 20A 3 Pole Miniature Circuit Breaker
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Description
Built for advanced control applications, the QO320-1021 combines standard thermal-magnetic protection with remote tripping capabilities. This 3-pole, 20A miniature breaker is ideal for environments requiring automated circuit disconnection. The device installs into Square D QO load centers and NQ panelboards. Because of the factory-installed shunt trip module, the complete assembly requires four pole spaces for proper mounting. Delivering a 10 kAIC rating, the unit features the Visi-Trip flag.Specifications
| Brand | Square D |
|---|---|
| Part Number | QO3201021 |
| Series | QO |
| Amperage | 20A |
| Poles | 3 |
| Mounting Style | Plug-On |
| Voltage | 120/240VAC, 48VDC |
| Phase | 3 |
| AIC Rating | 10kA @ 120/240VAC, 5kA @ 48VDC |
| Frame Type | QO |
|---|---|
| Terminal Type | Pressure Plate |
| For Use With | QO Load Centers, NQ Panelboards, NQOD Panelboards |
| Wire Gauge | 14-8 AWG (Al/Cu) |
| Max Wire | 8 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Available Options | Auxiliary Switch, Alarm Switch, Padlock Attachment |
|---|---|
| Accessories | Shunt Trip |
| Standards | CSA C22.2 No. 5, UL 489, HACR, NEMA AB 1 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator, HACR Rated |
Product FAQs
5 answersWhat does the -1021 suffix indicate on the QO320-1021 part number?
The -1021 suffix designates a factory-installed 120/208/240 VAC shunt trip module. This allows the breaker to be tripped remotely via an external control signal, such as a fire alarm panel or emergency stop button.
How many panel spaces are required to install the QO320-1021?
This assembly requires four pole spaces. While the breaker itself is a 3-pole unit, the factory-installed shunt trip module occupies one additional space in the load center or panelboard.
Which panelboards are compatible with the QO320-1021 breaker?
This plug-on breaker is designed exclusively for use in Square D QO load centers, NQ panelboards, and legacy NQOD panelboards. It cannot be installed in Homeline or competing manufacturer panels.
Can I use the QO320-1021 in place of a QOB320-1021?
No. The QO320-1021 features a plug-on mounting design, while the QOB320-1021 requires a bolt-on connection. You must verify whether your panelboard accepts plug-on or bolt-on breakers before purchasing.
How does the Visi-Trip indicator function on this breaker?
The Visi-Trip feature displays a highly visible red flag in the breaker window when it trips due to an overcurrent, short circuit, or a remote shunt trip command. This allows electricians to quickly identify the tripped circuit without testing each breaker in the panel.
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Reviews
Review summary
Customers rate this product 4.9 out of 5 based on 285 reviews.
Reviews Summary
Generated by AI from 100 most recent customer reviews
Last updated 6/13/26
Customers say these circuit breakers arrive quickly and work as described. Fast shipping and competitive pricing are frequently mentioned, with many noting same-day or next-day delivery. Users appreciate the wide inventory, particularly for hard-to-find older-style models unavailable locally. The products function reliably and arrive in good condition. Most customers report straightforward ordering and positive interactions. However, some experienced delivery delays or received incorrect items requiring reordering. A few noted concerns about condition upon arrival or customer service responsiveness.
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Rating
285 reviews
- GCGerard C.Verified BuyerReviewingSquare D QO130GFI - 30A GFCI Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/21/26Great !
I could not find the breaker in hardwood stores. Superbreakers took car of it in a week.
- RHRoy H.Verified BuyerReviewingSquare D QO280 - 80A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/17/26Square D QO280 - 80A 2 Pole Miniature Circuit Breaker
Exactly as described
- KWKevin W.Verified BuyerReviewingSquare D QO120 - 20A 1 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/15/26Great Price
Brand spanking new!
- CEchristopher e.Verified BuyerReviewingSquare D QO115PDF - 15A Dual Function Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/11/26My breakers
Had a hard time locating these breakers locally, when I did find 1 they wanted to charge me triple what superbreakers charged. Items delivered exactly when they said they would, were exactly what I ordered. Appreciated the ease of ordering, definitely my go to from this point on
- JCJerry C.Verified BuyerReviewingSquare D QO250 - 50A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/8/26Great quality
No issues